Hydraulic steering gear for ships



April 19, 1932. w. E. ROUSE 1,854,226

HYDRAULIC STEERING GEAR FOR SHIPS Filed May 17, 1929 INVENTOR WARREN E. R0055 ATTORN EYS Patented Apr. 19, 1932 UNITED STATES PATENT OFFICE WARREN E. ROUSE, OF WATERBURY, CONNECTICUT, ASSIGNOR TO THE WATEBBUBY TOOL COMPANY, OF WATERBUBY, CONNECTICUT, A CORPORATION OI CONNECT- HYDRAULIC STEERING GEAR FOR SHIPS Application filed May 17, 1929. Serial No. 368,980.

The principal object of this invention is to provide a new and improved hydraullc mechanism for operating the steering gears of ships.

heretofore been the practice to include in such apparatus an automatic pressure control device piped directly to the high pressure pipes leading to the cylinders or other motors which are directly connected to the rudder. This device was constructed and arranged so that when the pressure mounted beyond a certain predetermined point it would function automatically to cut down the output of the fluid pressure pump which furnishes the fluid to the operating motor of the rudder. But as heretofore constructed the device functioned to cut down the output of the pump when the vessel was steaming ahead, whereas when the vessel reversed the same pressure would tend to operate the device so that the output of the pump was increased. Obviously the lat ter result was highly undesirable.

Considered more specifically the pr1nc1- pal object of the present invention is to provide a new and improved apparatus by means of which the above mentioned disadvantage is eliminated and to devise an apparatus including a pressure control device that w1ll function to decrease the output of the pump when the rudder torque passes beyond a certain value, irrespective of whether the vessel is proceeding ahead or astern.

The above and other objects of the invention will appear more fully from the following more detailed description and by reference to the accompanying drawings forming a part hereof, wherein Fig. 1 is a plan view showing somewhat diagrammatically an apparatus constructed in accordance with the principles of the present invention; Fig. 2 is a side view partly in section of a satisfactory type of pump for use with the apparatus.

As shown in the drawings the numeral 10 indicates the rudder stock of a ships rudder which is connected by means of the tiller 11 to a ram 12. The ram 12 has its ends slidably mounted in a pair of fluid pressure cylinders 13, 14. Fluid under pressure is delivered to the cylinder 13, or the cylinder 14, through the pipes 15, 16, as will presently be more fully described, from the pump 17.

The pump 17 selected-for illustration is of the well known Waterbury type and comprises a driving shaft 18, connected by a coupling 19 to the armature shaft of an electric motor 20. The pump, as shown most clearly in Fig. 2 of the drawings, has secured to the driving shaft 18 thereof a rotary cylinder barrel 21 which is provided with a plurality of cylinders 22. Each of the cylinders 22 has slidably mounted therein a piston 23 connected by a piston rod 24 with a swash plate 25. The latter is connected in driving relationship with the driving shaft 18 by means of a universal joint 26 and is mounted for rotation within a tilting box 27 The tilting box may be adjusted angularly to the axis of rotation of the shaft 18 in either direction. When the tilting box is perpendicular to the shaft 18, as shown in Fig. 2, the pistons 23 will have no stroke and no fluid will be delivered by the pump. This is called the neutral position. When, however, the tilting box is moved in either direction from the perpendicular the pistons will be reciprocated. The extent of reciprocation and therefore the output of, or the volume of fluid pumped by, the pump will be increased as the degree of angularity of the tilting box is increased. For the purpose of adjusting the angle of inclination of the swash plate and tilting box the latter has formed integrally therewith a stub shaft 28, which projects into a rocking bearing 29 mounted for oscillation in a control shaft 30. These constructional details of the pump just described form no part of the present invention but are described in order that the operation of the apparatus may be more clearly understood.

It will be seen from the abo e that when the driving shaft of the pump is rotated by the motor 20 and when the swash plate and tilting box are inclined, that fluid will be pumped under pressure through either the 100 pipe 15 or 16 according to the direction and extent of adjustment of the swash plate and tilting box.

Connected to the ram 12 adjacent to the point of connection of the tiller 11 to said ram is one end of a bar 31 to the other end of which is connected one end of a link 32. The other end of the link 32 is pivotally connected to one end of a follow-up floating lever 33. The other end of the follow-up floating lever is adapted to be actuated by any suitable mechanism that includes-a manua ly operable control. In the particular constructional example shown in the drawings a telemotor 34 is indicated diagrammatically for actuating the lever 33. It will be understood that the telemotor 34 is under the manual control of a suitable hand operated device located in the ilot house of the ship. The telemotor 34 is s own as connected by means of a rod 35 with the end of the lever 33.

Pivotally connected to the floating lever 33 approximately at the center thereof, is one end of a connecting rod 36, the other end of which rod is pivotally connected to one end of a control floating lever 37. The other end of the control lever 37 has pivotally secured to it a piston rod 38 fixed to a piston 39. The piston 39 is mounted for reciprocation within a cylinder 40 and is normally held in a position approximately midway between the ends of said cylinder by a pair of springs 41, 42. Connected to the ends of the cylinder 40 on either side of the piston 39 are the ends of a pair of pipe lines 43, 44. The pipe line 43 communicates with a control pressure valve casing 45 adjacent to one end thereof, while the pipe line 44 communicates with said valve casing adjacent to the other end thereof. A third pipe line 46 communicates with the casing 45 substantially at the middle thereof and connects said casing with a shuttle valve 47.

Mounted within the casing 45 is a control pressure valve 48 having fixedly secured thereto a valve rod 49 which in turn is fixedly secured to or formed integral with the control shaft 30 of the pump 17. The control shaft 30 extends exteriorly from the casing of the pump upon the side thereof opposite to the valve rod 49 and is pivotally connected by any suitable means such as the yoke 50 with the middle of the control floating lever 37.

Slidably mounted within the bore of the shuttle valve 47 is a valve plug 51while the ends of the casing of the valve 47 are connected by the pipes 52, 53 with the pipes 15 and 16, respectively.

In the diagrammatic showing of Fig. 1 is included an expansion tank or reservoir 54 which is connected by means of the pipe 55 with one end of the valve casing 45. While the expansion tank 54 is shown in Fig. 1 of the drawings as located at the lower part of the figure, in actual practice, the tank 54 is located at the highest point of the fluid pressure system and contains a surplus supply of fluid such as oil, which surplus is provided for the purpose of maintaining all parts of the system completely filled with oil at all times.

The manner in which the device operates is as follows: Let it be assumed that the ram 12 is at rest and that the telemotor is actuated in a direction such as to produce a downward movement of the rod 35, as indicated by the arrow in Fig. 1. The ram 12 being stationary the follow-up floating lever 33 will be oscillated in the clockwise direction upon its pivotal connection to the link 32 as a fulcrum. This motion of the lever 33 wil be communicated through the connecting link 36 to the left hand end of the control lever 37 forcing the same downwardly. The right hand end of the control lever 37 will be held against movement by the piston rod 38, piston 39 and springs 41, 42, the lever 37 pivoting upon its connection to the piston rod 38 as a fulcrum. Downward movement of the control shaft 30 will be produced by the operations above described, thus causing the swash plate 25 and tilting box 27 of the pump to be moved from the perpendicular. Let it be assumed that motion of the control shaft downwardly as described will cause the pump 17 to deliver fluid under pressure to the pipe 16 and cylinder 14, thus producing an upwardmovement of the ram 12 as indicated by the arrow.

As the ram 12 moves upwardly the bar 31 is carried along with it and will cause, through the connecting link 32, a movement of the floating lever 33 in a direction such as to raise the connecting link 36 and thereby move the control floating lever 37 so as to return the control shaft 30 to neutral position. It will be understood that there will be a lag between the movement of the follow-up lever 33 produced by the telemotor and the movement of said lever by the ram 12, bar 31 and associated parts, with the result that after the telemotor effects acertain extent of movement of the lever 33 and control shaft 30, the pump will be automatically brought to neutral, no fluid will be pumped thereby and no further movement of the ram will occur, (except as hereinafter described) unless the telemotor is again actuated; but as the fluid within the cylinders 13, 14 will be trapped, as it were, the rudder will remain in the position to which it was set, until the telemotor is again actuated.

When the movement of the telemotor is continued, for example, in throwing over the rudder quickly to a hard over position, the movement imparted to the lever 33 by the telemotor will be to a certain extent neutralized, after the ram has commenced to move, by the connections 31, 32 of the ram to said lever.

The pressure within the pipe 16 is communicated through the pipe 53 to one end of the shuttle valve 47 moving the valve plug 51 therein to the right hand end of said valve. This will establish communication bet-ween the pipe 53 and the pipe 46, the pressure of the fluid being communicated through the pipe 46 to the fluid within the valve casing 45 of the control pressure valve. The valve 48 having been moved downwardly from the position shown in the drawings its lower land will have been moved out of alignment with the end of the pipe and the pressure of the fluid is communicated through the valve casing about the reduced central portion of the valve 48 and through the pipe 44 to the lower end of the pressure control cylinder 40.

As the rudder approaches an extreme position of inclination and the torque on the rudder stock mounts to an extent such that the operation of the pump at its full output 1) would tend to cause the pressure of the fluid in. the apparatus to increase beyond a predetermined amount and thereby place too great a strain upon the gear, the pressure control cylinder is caused to operate in the following manner: If the pressure within the cylinder 14 and pipe 16 rises beyond a predetermined maximum this pressure, communicated through the pipe 53, valve 47, pipe 46, valve casing 45 and pipe 44 will cause the piston 39 to be moved upwardly against the pressure of the spring 41, it being understood that the strength of the spring 41 is so proportioned that the piston 39 will be moved as above described only when the pressure of the fluid within the ram cylinder 14 exceeds such predetermined maximum. The upward movement of the piston 39 is communicated through the piston rod 38 to the right hand end of the lever 37, thus producing a movement of the lever 37 opposite to the movement imparted to it by the telemotor 34 and moving the control shaft 30 back to its neutral or off position. It will be noted that when the control, consisting of the piston 39 and cylinder 40, is caused to function as just described the movement of the control shaft is the resultant of movement of three different members, namely, the telemotor, the ram and the piston 39, the movement of the telemotor and ram being communicated indirectly through the follow-up lever 33 to the control lever 37 while the movement of the piston is directly communicated to said. control lever. It will thus be seen that while it is possible to overcome the neutralizing efi'ect of the rams movement on the follow-up lever, by operating the telemotor rapidly and thereby to bring the pump to, and maintain it at, its full output, as soon as the pressure of the fluid in the gear nears the predetermined maximum, the piston 39 will function immediately to move the control shaft towards neutral, irrespective of the speed of operation of the telemotor.

When the telemotor 34 is actuated 1n a direction opposite to that above described so as to cause the fluid from the pump 17 to be pumped under pressure through the pipe 15 to the ram cylinder 13, it will be obvious that the valve plug 51 of the shuttle valve 47 will be moved to the left hand end of the valve casing to place the pipes 52 and 46 in communication. The control shaft 30 having been moved upwardly and the valve 48 also moved upwardly communication will be established through the valve casing 45 between the pipes 46 and 43, the pressure of the fluid being exerted upon the upper end of the piston 39 so that if the pressure mounts beyond the predetermined value the con trol shaft will be moved downwardly to adjustthe pump automatically to its neutral osition.

While the follow-up lever has been described as actuated by a telemotor it will be understood that the invention is not limited in this respect but that any suitable operating mechanism, capable of either direct manual actuation or under manual control may be employed for operating the followup lever, the diagrammatic showing of the telemotor therefore being merely indicative of any suitable device. Likewise the invention is not limited in its application to a steering gear of the type wherein a ram or piston and cylinder is employed for actuating the rudder, the ram and cylinders shown also being merely indicative of any suitable fluid pressure actuated apparatus, and of which a rotary fluid pressure motor for example is an equivalent.

As to the above and other constructional details of the apparatus selected for illustration it will therefore be understood that the invention is not limited to such details but that many changes, variations and modifica-" tions may be resorted to without departing from the principles of the invention.

I claim:

1. In a ships steering gear, a rudder stock, fluid pressure actuated means for operating said rudder stock. a reversible variable delivery pump for delivering fluid under pressure to said means, a control for governing the rate and direcion of output of said pump, manually operable means, flexible linkage connecting said manually operable means with said control whereby the latter may be selectively operated under manual control, conduits connecting said means and pump, and means connected with said flexible linkage and arranged to operate the same independently of said manually operable means for automatically reducing the output of said pump when the pressure of the fluid within either of said conduits tends to exceed a predetermined maximum, comprisin a shuttle valve connected across said con uits, a pressure control cylinder and piston operatively associated with said control, and a prexure control valve interposed between and connected with said shuttle valve and cylinder and piston for controlling the flow of the pressure fluid to the latter.

2. A ships steering gear as set forth in claim 1 in which said pressure control valve is operatively associated with the control of the pump.

3. A ships steering gear as set forth in claim 1 in which springs are associated with the pressure control piston to hold it normally in a neutral position.

4. A ships steering gear as set forth in claim 1 in which the pressure control piston has associated therewith resilient means to hold said piston normally in a neutral position and to permit movement thereof in a direction to move the pump control and cut down the output of the pump when the pres.- v

sure in either of the conduits tends to exceed a predetermined maximum.

5. In a ships steering gear, a rudderstock, fluid pressure actuated means for operating said rudder stock, a reversible, variable delivery pump for supplying fluid under pressure to said means, said pump being provided with a control shaft, a floating control lever connected with said control shaft, conduits connecting said pump and fluid pressure actuated means, manually operable means flexibly connected with said floating lever, combined fluid pressure and spring actuated means connected to said floating lever, and means for automatically connecting said last named fluid pressure and spring actuated means with the conduit under pressure, comprising valve means for automatically establishing communication between said device and the one of said conduits under pressure.

6. In a ships steering gear, a rudder stock, fluid pressure actuated meansfor operating said rudder stock, a reversible, variable delivery pump for supplying fluid under pressure to said means, said pump being provided with a control shaft, a floating control lever connected with said control shaft, conduits connecting said pump and fluid pressure actuated means, manually operable means flexibly connected with said floating lever, combined fluid pressure and spring actuated means connected to said floating lever, and means for automatically connecting said last named fluid pressure and spring actuated means with the conduit under pressure, comrising valve means for automatically establishing communication between said device and one of said conduits under pressure, said valve means including a shuttle valve connected across said conduits, and a control pressure valve, interposed between and connected with said device and said shuttle valve for controlling the flow of pressure fluid to said device.

7. In a ships steeringv gear, a rudder stock, fluid pressure actuated means for operating said rudder stock, a reversible, variable delivery pump having an adjustable control shaft for varying or'reversing its output, conduits connecting said fluid pressure actuated means arid said pump, manually operable means for actuatlng said control shaft, a pair of floating levers connected with each other and constituting a flexible connection between said manually operable means and said control shaft, connections from one of said levers to said rudder stock, and an automatic fluid pressure device connected with the other of said levers actuated by fluid pressure from one of said conduits for automatically restoring the pump to neutral position when the developed pressure mounts beyond a predetermined value.

8. Ina ships steering gear, a rudder stock, fluid pressure actuated means for operating said rudder stock, a reversible, variable delivery pump having an adjustable control shaft for varying or reversing its output, conduits connecting said fluid pressure means and said pump, a floating follow up lever, a manually controlled device for operating said lever, connections between said lever and rudder stock, a floating control lever connected to the control shaft of the pump, connections between said control lever and said follow-up lever constituting with said levers a flexible connection between said manually controlled device and said control shaft whereby the latter is selectively operated, and a combined fluid pressure and spring actuated device operated by fluid pressure from one of said conduits connected to said control lever and controlling the latter independently of said manually controlled device.

9. In a ships steering gear, a rudder stock, fluid pressure actuated means for operating said rudder stock, a reversible, variable delivery pump having an adjustable control shaft for varying or reversing its output, conduits connecting said fluid pressure actuated means and said pump, a floating follow-up lever, a manually controlled device for operating said lever, connections between said lever and rudder stock, a floating control lever connectedto the control shaft of the pump, connections between said control lever and said follow-up lever constituting with said levers a flexible connection between said manually controlled device and said control shaft whereby the latter is selectively operated, and a combined fluid pressure and spring actuated device connected to said control lever and connections including valve means for automatically placing said last named device in communication with the one of said conduits under the greater pressure for automatically restoring the pump to neutral position when the developed pressure mounts beyond a predetermined value.

10. In a hydraulic driving mechanism, a reversible, variable delivery fluid pressure pump having an adjustable control shaft for varying or reversing its output, fluid pressure actuated means connected to the member to be driven, conduits connecting said pump with said means, a floating control lever connected to said control shaft, means under manual control for actuating said lever, a fluid pressure device connected with said lever and efli'ective thereon independently of said manually controlled means, and means for automatically placing said device in communication with that one of said conduits in which at any time the fluid is under the greater pressure, said last named means including a valve connected with said control shaft for controlling the flow of pressure fluid to said device.

11. In a hydraulic driving mechanism, a reversible, variable delivery fluid pressure pump having an adjustable control shaft for varying or reversing its output, fluid pressure actuated means connected to the member to be driven, conduits connecting said pump with said means, a floating control lever connected to said control shaft, means under manual control for actuating said lever, 21 fluid pressure device connected with said lever and efl'ective thereon independently of said manually controlled means, and means for automatically placing said device in communication with that one of said conduits in which at any time the fluid is under the greater pressure, said last named means including a shuttle valve connected across said conduits and a valve connected to said control shaft interposed between said device and said shuttle valve for controlling the flow of pressure fluid to said device.

In testimony whereof I have hereunto set my hand.

WARREN E. ROUSE. 

